TESTED: Mossberg 940 Pro Tactical SPX

The new Mossberg 940 Pro Tactical SPX semi-auto 12-gauge may be the most purpose-driven, mission-focused shotgun ever to roll off the factory line

by Rob Reaser

It’s easy to become jaded in this business when you see, time and again, a lot of fanfare and hoopla being drummed up by firearm manufacturers for new products that are little more than minor variations on an all-too-familiar theme. It becomes the “boy who cried wolf” syndrome. But every once in a while, a manufacturer delivers a variant of a long-proven firearm platform that makes you stand up and go, “Woah…”

Such is the case with the new Mossberg 940 Pro Tactical SPX. This is a semi-auto 12-gauge that addresses absolutely every need and nuance right out of the box. That’s a bold statement, for sure, and I’m standing by it.

The only way to truly understand the qualities of a gun, good or not so much, is through hard-use application of all the various scenarios that said gun may be tasked with. I was able to do exactly that recently while taking an accelerated 260 Defensive Shotgun class at the famed Gunsite Academy in Paulden, Arizona.

The Real Test

Over the span of three days, I got to know the Pro Tactical SPX intimately, courtesy of the fine course instruction provided by Gunsite Rangemaster Mario Marchman and Instructor Chris Currie. Applying the crawl, walk, run methodology, the course began with such basics as operation control, stance, grip, presentation, and reloading techniques before moving onto increasingly complex scenarios, timed modules to induce stress, and eventually more challenging target engagements such as shooting and reloading from the ground, working barricades, and the highlights of proper room clearing.

Tested: Mossberg 940 Pro Tactical Spx — Gunsite Instructor Chris Currie demonstrates how to clear a hallway without becoming a target.

Aside from the frequent breaks between stages to ensure adequate hydration in the high Arizona desert, our group’s barrels rarely had a chance to cool off. All of that, punctuated with 400-something rounds sent downrange, will certainly highlight the good, the bad, and the ugly of any defensive shotgun. If there is a deficiency in the firearm, this course will reveal it in short order. It will also reveal the durability and reliability of the gun if such attributes are imbued in the design and construction. Regarding Mossberg’s 940 Pro Tactical SPX, the gun proved itself not only to be a solid fighting shotgun but also to be a gun crafted not as a line extension afterthought but one that addresses all the needs of the defender.

How so?

Nine times out of ten, experienced defensive shotgunners will immediately look to the aftermarket to “complete” their new shotgun. This almost always means adding rail modules or a new handguard, upgrading the sights, adding some type of shell holder or saddle, and perhaps modifying the stock or adding a sling swivel mounting system. A first glance at the 940 Pro Tactical SPX might hint that the same would need to be done with this 12-guage brute.

Nope.

So, let’s examine why that is the case by taking a point-by-point tour of Mossberg’s latest (greatest?) semi-auto scattergun.

Beast Control

Those who have had to use a semi-auto shotgun in a defensive situation or who have taken quality defensive training understand the value of large and robust operational controls. Fine motor skills tend to fall to pieces under stress — even if it is only time-induced stress. To minimize the chance of fumbling during high-stress speed reloads (remember…a defensive shotgun is hungry and needs continuous feeding), Mossberg added a LARGE and aggressively knurled bolt knob to the Pro Tactical SPX. This is backed up by an equally hefty and ergonomic bolt release.

The value of the enhanced bolt release design was immediately evident during speed loading drills, where the gun runs dry, the threat remains, and you must reload subsequent shells directly into the loading port. Drop the shell into the port and hit the bolt release to lock into battery. The bolt release lever measures around 1.25-inches long. With the lever pivoting on the back end of the assembly, the forward curved portion helps roll your actuating finger so it can apply optimal leverage with even a poor or hasty finger position and quickly close the bolt. That is important when you need to get back into the fight. Contrast this excellent design to the more conventional release button, where the button is smaller and requires a straight push toward the receiver to close the bolt. There is no arguing from me as to which design is best.

It is little details like this that make the Pro Tactical SPX a standout in an already crowded field of defensive shotguns.

As for the oversized bolt handle, I really appreciated this when training to transition mid-fight from buckshot to slug ammo. In this scenario, buckshot isn’t getting the job done to neutralize the threat, so you must insert a slug round. Yet, working a semi-auto action gun, you never have an open chamber because there is always a round in the chamber if there is ammo in the magazine tube.

The solution is to feed a slug round into the magazine through the bottom loading port. Next, manually cycle the bolt to eject the buckshot that is in the chamber and chamber the slug round. When doing this operation under stress, the large bolt handle makes quick work of the transition. Sweep your hand back along the receiver, catching the bolt handle with your palm, and you’re in business.

The same applies if you keep your gun stored in “cruiser-ready” mode (magazine loaded, chamber empty, safety on) and need to chamber a round quickly.

Another oversized-is-better component is the safety selector. Mossberg has wisely (and historically) always favored the tang-mounted safety selector position. It only makes sense because you move the selector to the fire position only when you start raising the gun to the target and, by default, your thumb is already in position on the grip to easily push the lever forward. Thus, the tang position makes this the ideal safety configuration from the start. Add the enlarged safety selector with aggressive, robust texturing for easy manipulation under stress and you have the best of the best design for a defensive shotgun.

Continuing with the operational refinements of the 940 Pro Tactical SPX, we find a loading port that is among the most, if not the most, finger-friendly out there. You’ll also note the generous beveling along the port edge — perfect for funneling shells into the port during speed reloads.

But about that finger-friendly thing…

We all have experienced “loading bite” when filling a magazine tube — when sharp edges along the mouth of the tube and the front of the elevator pinches and grabs your loading thumb. Somehow, Mossberg managed to do what few shotgun manufacturers seem able to do, and that is get rid of the bite. It just doesn’t do it. I have run my thumb in and out of the magazine tube — both quickly and with slow deliberation — who knows how many times now and have yet to get “bit.” For this alone, the 940 Pro Tactical SPX deserves high praise.

Customize Your Ergonomics

Now let’s shift our attention to the ergonomics of the gun. I’ll start by noting that for my medium build, I find most defensive and general-purpose shotguns rather unwieldy. Having done most of my high-volume shooting with the sleek AR platform rifle, jumping onto a shotgun is not unlike a good, ol’ fashioned Scottish caber toss for me. My biggest problem is that the length-of-pull is usually too long for comfort. I expected the same when I unboxed the Pro Tactical SPX, but removal of the two spacers shortened the LOP to the just-right position.

As for the butt pad, I found it to be super comfortable and super squishy under recoil. In the three days of steady, high-volume shooting of birdshot, buckshot, and slugs, my shoulder never became sore or bruised.

The rubber that makes up the pad is interesting. Some rubber pads are so “sticky” that they easily drag on clothing, making fast mounting a tad difficult when wearing a loose shirt. This pad, though, does not have that high-drag quality; neither is it slippery, which could cause you to lose your solid mounting position during rapid fire exercises. Instead, the friction finds that happy middle ground of just enough but not too much. Some of the butt pad’s traction comes courtesy of integrated traction grooves.

Another important feature to point out here is the sweeping contour at the heel of the pad. This is a deliberate design intended to further prevent clothing snag when raising the gun to your shoulder.

Again…details.

Something else you’ll find in the Pro Tactical SPX box that is often lacking in defensive shotguns is a means of adjusting drop and cast. The gun comes with a combination of drop at heel (DAH) spacers and retention plates ranging from a .250-in. drop to a .375 rise. This adjustment comes in handy for achieving optimal eye alignment behind the sights or when fitting a red dot. Left and right cast spacers provide the solution for horizontal eye alignment.

Purpose-Driven Furniture

Moving further up the stock, we have a well-executed grip. I find it to offer comfortable yet solid hand placement while ensuring a good finger position on the trigger shoe with my medium-sized hands. What really stands out, though, is the grip texturing. It is surprisingly aggressive yet not at all uncomfortable for long shooting sessions. As for weapon retention (the important stuff), it works great and is a huge benefit when holding the gun one-handed for tactical reloads.

Also in the spirit of weapon retention is the inclusion of QD sling swivel cups integrated into the left and right sides of the buttstock. A rapid-adjust sling should be considered mandatory gear for a defensive shotgun for several reasons: 1) a slung weapon is more difficult to be taken from you, 2) a sling frees your hands, if need be, and, 3) a sling can be helpful for longer-distance shot stabilization. Having the sling swivel cups closer to the stock’s heel allows you to maintain a proper “gun up” orientation when carrying the shotgun cross-body.

It’s difficult to pick out a “highlight” in a firearm that has so many, but without doubt, the Pro Tactical SPX’s forend can claim this status. Not only does it rank high on the ergonomic scale, but there are also a lot of intelligent design functions built into it.

As you can see, the texturing found on the stock also extends to the forend. You’re simply not going to slip around on this piece. Nevertheless, Mossberg designers added a modest hand stop at the front of the forend to prevent the gun from slipping out of the support hand under recoil…just in case.

The top half of the forend is especially noteworthy. Ventilation slots add a little something to keep the barrel cool. Should the barrel get toasty, integrated heat shielding along the top of the forend wrap around the sides of the barrel to help prevent finger burn.

Accessory-Friendly

Ironing out a defensive shotgun demands, for most users, custom placement of sling swivel mounts and the addition of a light. Here, the Pro Tactical SPX stands ready. There are two M-LOK slots on the left and right side of the forend and one on the bottom. Toward the back of the forend there are integrated QD sling swivel cups, one on each side. Mossberg further buttressed these cups to withstand the carry weight.

Once more…details.

If you need more choices in accessory placement, look no further than the two-piece barrel clamp. Each side hosts an M-LOK slot, so you can choose a far-forward sling mounting point, if you like, or you might find it to be the ideal position for your light. For me, having Streamlight’s tidy and super-bright TLR-7 HL-X light mounted to the bottom of the forend is perfect. It keeps the light out of the way of corner bumps (versus side mounting) and places the switches within easy finger reach of my support hand.

Sighting Options

Defensive shotguns are, by nature and application, hard-use tools. In other words, they tend to get bumped and banged around more than any other firearm during routine training or professional use. With this in mind, Mossberg integrated protective wings for the fiber-optic front sight into the barrel. The rear ghost ring sight assembly, although completely removeable from the receiver, also features protective wings. In short, the Pro Tactical SPX open sights are well-guarded.

Much as I like a solid ghost ring sight set for defensive shotguns, I, like many others, am sold on the value of red dots for fighting shotguns. So, it should be no surprise that Mossberg made accommodation for red dot use on the Pro Tactical SPX. I’m not talking about mounting a rail to the drilled-and-tapped receiver and sticking on a red dot. No, Mossberg instead has cut the Pro Tactical SPX’s receiver to directly mount micro optics with the RMSc footprint.

This is a big deal for those who understand shotgun dynamics because shotguns are designed to be mounted with the eye low to the bore axis and the cheek firmly planted on the stock. Having a direct-mount optic cut on the Pro Tactical SPX means you can get that optimal eye-behind-the-barrel mounting position since the micro red dot sits so low on the receiver. The Holosun HS407K X2 seen here illustrates the low bore axis position of the direct-mount design.

The gun does come with adapter plates for mounting optics with RMR, Docter, and Leupold footprints, if one of those are your flavor.

And There’s More…

In another “Did they have to think of everything?” example, the Pro Tactical SPX comes from the factory with a Vang Comp 6-shot shotshell carrier pre-installed. While the gun’s 7+1 capacity is a great start, additional on-board ammunition should be considered mandatory. I like this carrier because it held the ammo securely throughout the 3-day Gunsite course and because it secures to the side of the receiver with a hook-and-loop attachment. This means I can carry one or more pre-loaded carriers on me and when one runs dry, rip it off the gun and slap a full one in its place.

The Pro Tactical SPX has a cylinder bore barrel that is profiled and threaded to accept Mossberg’s Accu-Choke system. The gun comes with a cylinder choke tube and wrench.

Beneath the barrel you see the magazine tube that holds seven rounds of 2-3/4 shotshells.

The magazine tube is a one-piece unit covered with a detachable sleeve at the front. Unlike other 940 models, the Pro Tactical SPX captures the magazine tube spring with the same cleanout-style magazine cap as you’ll find in Mossberg’s 590-series tactical pump-action shotguns, meaning you don’t have to remove the spring during the disassembly process in order to clean the gun and gas system.

To clean, simply unscrew the sleeve from the magazine tube and remove the barrel and gas assembly. Pull the bolt handle out of the bolt and the bolt/slide assembly comes right out. Two pins secure the trigger assembly in the chassis. Pop these out, remove the trigger assembly, and the gun is stripped and ready to clean. Easy stuff.

The Wrap

Mossberg offers the Pro Tactical SPX in five variations:

8-shot combo w/Holosun optic
8-shot in FDE Cerakote, OD Green Cerakote, and Matte Blue
5-shot in Matte Blue

With MSRPs ranging from $1,190 for the 5-shot model to $1,371 for the combo version, the Pro Tactical SPX is well-priced…meaning, for the proven performance you get and the many features that make this gun out-of-the-box ready with no huge aftermarket shopping required to get it how you want it, the asking price is more than reasonable.

We don’t get the opportunity to put many guns through the kind of exhaustive testing like I did at Gunsite with the Mossberg Pro Tactical SPX. As mentioned earlier, our group put around 400 rounds downrange each during the 3-day course. When I brought the gun home for photography and upcoming content (stay tuned), I took it apart for cleaning. It was quite evident that this firearm had been used for at least one or two of the prior Gunsite courses I knew about and had been driven hard and put up wet. My guess is that it may have had 400-800 rounds put through it without cleaning (and sitting for months in-between) before it was my turn. Still, it never failed me…all the way to the last shot of the last day.

You can’t ask for more dependability than that for a home defender.